Pharmacological profile of a new orally active progestational steroid: Org 2969. (Abstract only)

The pharmacological profile of a new orally active progestational steroid Org 2969 (13-ethyl-11-methylene-18 19-dinor-17alpha-pregn-4-en-20-yn-17-ol) is presented. Org 2969 showed strong progestational activity in the Clauberg-McPhail test after a total oral dose of 15 mcg. After oral administration of 100 mcg no estrogenic activity could be shown in the Allen-Doisy test and a daily oral dose of 500 mcg fully abolished the estrogenic effect of a daily sc dose of .2 mcg estradiol-17beta on vaginal cornification in spayed rats. After daily oral administration the androgenic activity of Org 1969 as shown in the Hershberger test appeared to be very weak. Org 2969 has .074 and .019 times the androgenic activity of methyltestosterone using as parameters increase in the weight of seminal vesicles and ventral prostate. Org 2969 at 2 X 250 mcg/day orally inhibited spontaneous ovulation in rats and a single oral dose of 1 mg inhibited coitus - induced ovulation in rabbits. Postcoital treatment for 8 days with 2 X 60 mcg/day of Org 2969 did not disturb transport and nidation of fertilized ova in the mated rat. After daily administration for 8 days of 125 mcg of Org 2969 (orally) or 60 mcg of Org 2969 (sc) to mature estrous rabbits cervical function was altered (inhibition of sperm transport) resulting in a high percentage of unfertilized tubal ova observed 36 hours after human gonadotropin-induced ovulation and vaginal insemination. (Full text)